In working through, make a decision and stop thinking. In other words, you move the decision process and go on. It's going to take determination to just make the decision and focus "in the moment" for the decision.
Your particular pattern of thought you are already aware of "over". So, use a different word to help you focus on "now" - make a choice and go on to the next part.

I seem to second guess myself a lot too. Sometimes you just have to make a decision that just feels right and stick with because if you think about it a lot, you will change your mind.

Hi Hammar,
I can relate to the issue of overthinking. It's exhausting worrying about something that typically doesn't ever happen. For me, it manifests itself in other ways: worrying that I will bother a friend if I call her up to hang out, worrying I will annoy my friends or appear clingy if I talk with them too much or seek them out too often, and worrying that if I shared my opinion in a group that everyone would begin to think less of me. In counseling, I learned a tool that was helpful. My counselor said, "When you find yourself worrying/overthinking about something, take a moment to identify what you are telling yourself." In those situations, the belief I was buying into and the underlying message was, "I'm not likable" and "my opinion isn't valuable." My counselor suggested that I begin telling myself the opposite of those messages, "I am likable." "My opinion matters and has value." She suggested I tell myself this not only in those overthinking moments, but all throughout the day. While it was hard to believe these things about myself right away, over time, I have begun to truly believe them, just as I had been buying into those negative messages all those years.

What kinds of messages are you telling yourself when you're worrying about leaving class early? "I'm not committed to the class or at least I might be perceived as that," "I'm not a good student or the teacher might assume that of me," or "I don't deserve to be here"??? These are just guesses of what you might be thinking, but whatever the negative message is that you're telling yourself, try telling yourself the opposite: "I'm a good student and leaving early is not a reflection of my work ethic" or "I deserve to be here just as much as everyone else." Even if it does not feel true, try telling yourself that anyway. What you're currently doing doesn't seem to be helping you with your anxiety, so why not try some positive self-talk?

Wishing you the best as you work through this issue. It can definitely be debilitating and prevent you from getting the support you need and also from having some really great life experiences, but reconstructing how you perceive yourself may be a helpful place to start :)

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